Andrew a



UNITED STATES PATENT OFFICE.

ANDREW A. MsER, OE NEw YORK, N. Y.

BOOK-RULER.

Specification of Letters Patent No. 27,464, dated March 13, 1860.

To' all whom it may concern.'

Be it known that I, ANDREW A. Msnn, of the city, county, and State of New York, have invented a new and useful Book-Ruler;

Vand I do hereby declare that the following ruling horizontal lines on blank books ot every description which with the present straight rulers is found to be a very diiiicult task on account of the natural curvature of the leaves, especially in a large thick book, as they approach the back otl the book.

My invention provides for making a straight line the entire width of the leaf on either side of the page or as near to the opposite leaf, or back of the book, as is necessary, with the saine facility as in making a line on a level surface.

For this purpose my invention consists in curving the ends of a ruler in opposite curves and leveling the edges of the ruler in the usual manner so that it may be used either side up.

To enable those skilled in the art to fully understand my invention I will proceed to describe its construction, and the manner of using it. y

In the drawings Fig. 2 represents a ruler of any suitable length, thickness or width with the ends, A A', bent in opposite directions, the curves of which may be gentle, or quite abrupt, but the degree of curvature' is immaterial, for almost any curve approaching that shown by the drawings can be adapted to the surface of an open book. The edges, a a, of the ruler are beveled in the usual manner of ordinary straight rules.

The material ot' which my rulers are made will, ot course, be optional with the maker: they may be made ot hard wood, and the ends bent by stean'iing and curving, or they may be made of vulcanized rubber, or even ot metal, it desired. That portion ot' the ruler between the curves should be straight like any ordinary ruler so that it may be used, if suiiicientlv long, for rulingl perpendicular lines on a book by letting one curved end project down and over the edge of the book. Its application to one side of a book is clearly represented by F l, of the drawings; for the opposite side the opposite curved end is used and the opposite side of the ruler is turned down.

IVith such a ruler as this a straight line may be drawn with an ordinary pen over the curved surface of an open ledger with ease and facility,

Having thus described my invention what I claim as new, and desire to secure by Letters Patent is The book ruler with curved ends, herein described and represented.

ANDREW A. MosER.

Witnesses IVM. THOMPSON, CHS. HUGHES. 

